Constant velocity joint coupling

ABSTRACT

Constant velocity joint coupling includes one joint half-formed with a plurality of axially parallel concave race surfaces defining a number of cylindrical spaces therebetween; and another joint half-including a hub having at least three arbors extending radially in stellate form therefrom, and a spherically convex roller-shaped joint member rotatably and axially displaceably mounted on each of the arbors, the joint members being received respectively in the cylindrical spaces, the hub having a free end formed with a spherically convex axial bearing surface having a center of curvature located at the point of intersection of the longitudinal axis of the hub and the axes of the joint members, and the one joint half being formed with a support bearing surface cooperatively engaging the axial bearing surface.

United States Patent 1 a ae ar 2,615,317 [0/1952 Rzeppa CONSTANTVELOCITY JOINT COUPLING 7 Claims, 3 Drawing Figs.

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References Cited UNITED STATES PATENTS Inventor Appl. No. Filed PatentedAssignec Priority 3,452,558 7/1969 Cull et a].

AWTIWMCT: Conetant velocity joint coupling includes one jointhalflformed with a plurality of axially parallel concave race eurfaceedefining a number of cylindrical apaces therchetween; and another jointhalflincluding a hub having at least three arhore extending radially inetellate form therefrom, and a spherically convex rollerehaped jointmember rotatably and axially dieplaceably mounted on each ofthe arbore,the joint membera being received respectively in the cylindrical epacea.the hub having a free end formed with a epherically convex axial bearingsurface having a center of curvature located at the point ofintersection of the longitudinal axie of the hub and the axee of thejoint members, and the one joint half being formed with a aupportbearing surface cooperatively anaemia the axial hearing eurtace.

PATENIEU AUG 3 l9?! SHEET 1 0F 2 SQE PATENTEB AUG 31971 3 595, 75

SHEET 2 BF 2 CONSTANT VELOCTTY JOllNT COUPLING My invention relates toconstant velocity joint coupling and more particularly to such couplinghaving one joint half with at least three stubs or arbors extendingradially in stellate form from a hub, a spherically convex roller-shapedjoint member being rotatably and axially displaceably mounted on therespective stubs, and another joint half having axially parallel concaverace surfaces defining a number of cylindrical spaces therebetween inwhich the joint members are respectively received. Such a joint couplingusually affords mutual relative displacement of the two joint halves.

When-using such couplings in some situations, the necessity has arisenfor bracing the two joint halves of the coupling axi allywith respect toone another while, however, still retaining the displaceability ormobility of the bending angle and the constant velocity or synchronismof the joint halves.

It is accordingly an object of my invention to provide constant velocityjoint coupling wherein the joint halves are braced axially relative toone another while maintaining displaceability or mobility of the bendingangle of the joint and the constant velocity or synchronism of the jointhalves.

With the foregoing and other objects in view, I provide, in accordancewith my invention, constant velocity joint coupling comprising a pairofjoint halves, one of the joint halves being formed with a plurality ofaxially parallel concave race surfaces defining a number of cylindricalspaces therebetween; and the other of the joint halves including a hubhaving at least three arbors extending radially in stellate formtherefrom, and a spherically convex roller-shaped joint memberrotatabl'y and axially displaceably mounted on each n the one joint halfbeing formed with a support bearing surface cooperatively engaging theaxial bearing surface.

With a constant velocity joint coupling of such construction, axialrelative movements of the joint halves are avoided yet, whilemaintaining the constant velocity or synchronism of v the joint halvesas heretofore, displaceability or mobility of the bending angle of theboth joint halves relative to one another is ensured. Such a jointcoupling is employed advantageously for upright or vertically disposedstructure wherein the upper joint half is brewed or supported by theaxial bearing surface at the lowerjoint half.

- if the axial forces to be absorbed by the joint coupling arecomparatively small, in accordance with a further feature of myinvention, the support bearing surface cooperatively engaging the convexaxial bearing surface of the other joint half has a flat or planarconstruction.

7 in accordance with another feature of the invention, the supportbearing surface cooperatively engaging the convex axial bearing surfaceis formed at the inner end face of a central cover sealingly secured atthe side .of the one joint half to which the shaft associated with thatone jointhalf is attachable; The'cover thus sealingly closes off theinterior of the joint from the exterior so that both the joint membersand the race surfaces as well as the axial bearing surfaces are able tobe lubricated in common with the same lubricating means such as greaseor the lilte.

in accordance with a further advantageous feature of my invention, lprovide at the free end of the hub facing the point of intersection ofthe longitudinal axis of the hub and the axes of the joint members, anannular spherically concave axial bearing surface having a radius ofcurvature equal to the distance of that axialbearing surface from theintersection point, and the one joint half is provided with aspherically convex support bearing surface having substantially the sameradius of curva ture as the axial bearing surface and cooperativelyengaging the latter. With this construction, axial relativedisplacements of the joint halves in opposite directions are prevented.

in accordance with still another feature of the invention, the

axial bearing surfaces are formed on a bearing head secured on anextension of the hub resembling a shaft stub, the bearing head beingreceived with clearance between the support bearing surfaces formed atthe one joint half. Clearance is necessary because, when the jointhalves are bent with respect to one another, a givencentral displacementcan occur which can cause binding or jamming between the joint halves ifno clearance were provided.

Other features which are considered as characteristic for the inventionare set forth in the appended claims.

Although the invention is illustrated and described herein as embodiedin constant velocity joint coupling, it is nevertheless not intended tobe limited to'the details shown, since various modifications andstructural changes may be made therein without departing from the spiritof the invention and within the scope and range of equivalents of theclaims.

The construction and method of operation of the invention, however,together with additional objects and advantages thereof will be bestunderstood from the following description of specific embodiments whenread in connection with the accompanying drawings, in which:

FlGS. la and 112 are longitudinal half sections of two differentembodiments of the joint halves of a coupling constructed in accordancewith my invention; and

P16. 2 is a cross-sectional view taken along the lines ll-ll in FIGS. laand lb.

Referring now to the drawings, there is shown in both embodiments ofFIGS. la and lb a joint coupling constructed in accordance with myinvention having one joint half 1 provided with three arms 2 that arespaced at equal intervals of 120 about the periphery of the one jointhalf 1 and another joint half 3 formed of a hub 4 (FIG. la), 4 (FIG. lb)and three radially extending stubs or arbors d, also peripherally spacedat equal intervals of 120 on which joint members 6 are rotatably andlongitudinally displaccably mounted, respectively. The arms 2 are formedwith arcuate lateral faces '7 which extend in the axial direction of thearms 2. Respective lateral faces of the arms 2 located adjacent oneanother in the peripheral direction of the joint half 3 are disposedopposite one another and define therebetween :a cylindrical spaceextending parallel to the axis of the joint half 1. Thus, the respectivelateral faces 7 of the adjacent arms 2 may be considered as beingdisposed on common axially extending surface of a cylinder. The jointmembers s are spherically curved like the cylinder surface defined bythe lateral faces 7 of the adjacent arms 2, the radius of curvature ofthe surface of the joint members ti being the same as the radius ofcurvature of the cylindrical space defined by the lateral faces 7 of theadjacent arms 2, each of the joint members 6 being accordinglyaccommodate'd between the lateral faces 7 of adjacent arms 2. Because ofthis arrangement, the two joint halves l and 3 are displaceableangularly and longitudinally relative to one another.

For further description of constant velocity joint couplings of thisgeneral type, reference may be had to the copending application of H. J.l ileinschmidt et al. Serial No. 887,158, filed on or about Dec. 22,1969, and assigned to the same assignee as that of the instantapplication.

The arms 2 are enclosed at the free ends thereof by a ring 8 which, atan end thereof directed toward the joint members 6, is provided withthree radially inwardly extending projectors '9 spaced at equalintervals of l20 about the periphery of the ring 8. The width of each ofthe projections Qcorresponds sub stantially to the dimension of the arms2 measured in peripheral direction of the joint half l, nd the thicknessof the projections 9 corresponds substantially to the width of aperipheral groove Ml formed in the joint half l and extending across thearms 2 thereof.

To assemble the ring with the joint halves, the ring b is disposed withthe projections 9 thereof in the position shown in phantom in FlG. 2,between the arms 2 of the joint half l and is then pushed forwardlytoward the joint halfl, i.e. the

lefthand side-of la and lb until the projections 9 are in alignment withthe annular groove 10. The ring 8 is then rotated relative to the jointhalf 1 so that the projections 9 are angularly displaced from thephantom position thereof to the solid line position 9 thereof shown inFlG.2, wherein the projections 9 are each received in respectiveportions of the annular groove provided in the arms 2, thereby forming abayonetlike jointtherewith. After the ring 8 has been rotated into thesolid line position thereof shown in FIG. 2, it is secured againstrotation relative to the arms 2 by tightening a setscrew 43 which bindsthe ring 8 to the joint half '1. At an end of the ring 8 directed awayfrom the joint members 6, the ring 8 is reduced in diameter in order toprovide a support surface 42 i for the radially outer end of a flexibleroll diaphragm 38, the

inner end of the roll diaphragm being fastened to the hub 4. One end ofa sleevelike covering 39 is fastened by screws 40 to the outerperipheralsurface of the ring 8, and covers the arms 2 and the spacestherebetween, the other end of the sleevelike covering 39, as viewedfromthe free ends of the arms 2, is seated on a peripheral surfaceportion of the joint half 1 with a spherical convex bearing surface 36.The center of curvature of the bearing surfaces 35 and 36 is located atthe point of intersection M of the longitudinal axis of the hub 4, 4'and the axes of the joint members 6 so that the radii of curvature ofthe surfaces 35 and 36 corresponds to the distances respectivclytherefrom along the axes of the hub 4 to the point M.

The bearing surface 35 cooperatively engages an annular support bearingsurface 35' formed on a ring 37 and disposed coaxially to the opening32, the ring 37 being secured by any suitable means to the inner wallsurface of the cavity 30 at the right-hand side thereof, as shown inFIGS. la and lb.

The spherical convex bearing surface 36 cooperatively engages a flat orplanar support-bearing surface 36 formed at the base of the cover 31,31'.

Clearance is provided between the bearing surfaces 35 and 35', on theone hand, and 36, 36, on the other hand, in order to accommodate anydisplacement of the hub 4 that mayarise located at the base of the arms2. Further details of the conprovided at the open end thereof at theleft-hand side of FIG.

1a with an internal thread in which an externally threaded end 13 of ashaft stub 14 is screwed so as to provide an extension of the hub 4. Theshaft stub 14 is centered with respect to the hub 4 by a slotted orsplined pin 15.

- in the embodiment of FIG. 1b, the hollow hub 4 is connected to theshaft 11', associated therewith, by means of intermeshing radialserrations or teeth 12', formed on the end faces thereof, and athrough-bolt 16 having at the right-hand end thereof, as shown in FIG.1b, a shoulder portion 17 hearing on the rear face of a flange 18 formedon the shaft 11 and carrying the respective teeth 12. At the end 19 ofthe through-bolts 16, an external thread is formed, which meshes with aninternal thread provided in a hollow end 13' of a shaft stub 14 formingan extension of the hub 4'. The shaft stub 14' is provided with a flange15' through which it is in abutting engagement with and braced againstthe end face at the open end of the hub 4' wherein the end 13 isfittingly received. Obviously, it is also within the scope of myinvention to provide a hub and shaft stub of one-piece construction.

in the one joint half 1 there is formed, in the portion thereofextending away from the arms 2, a central cavity having an opening 32 atthe right-hand side thereof, as viewed in H08.

1;: and lb. The shaft stub I4, 14" projects with marked clearancethrough the opening 32 into the cavity 30. A bearing head 34 threadedlysecured to the free end of the shaft stub 14', 14',-and fastened by asetscrew 38, is received in the central cavity 30. A cover 31 31sealingly closes the cavity 30. at the left-hand side thereof, as viewedin FIGS. 1a and lb. The cover 31 of the embodiment of FIG. 1a, securedby a circlip or snap r'ing 41, is provided, at the side thereof facingaway from the cavity 30, with a suitable centering device such as isrequired for the attachment of a spring lock or rapid closure coupling.The cover 31' in the embodiment of FIG. 1b is of flat or planarconstruction and is sealingly bolted to the joint half 1.

At the side thereof facing the opening 32 of the central aperture 30,the bearing head 34 is formed with a spherical concave bearing'surfaceand, at the side of the bearing head 34 facing the cover 31, 31', thebearing head is formed during use of the joint due to bending thereof.The one joint half 1 is thereby reliably supported or braced on twosides of the other joint half 3 for all possible bending angles of thecoupling halves.

lclaim:

l. Constant velocity joint coupling comprising a pair of joint halves,one of said joint halves being formed with a plurality of axiallyparallel concave race surfaces defining a number of cylindrical spacestherebetween; and the other of said joint halves including a hub havingat least three arbors extending radially in stellate form therefrom, anda spherically convex roller-shaped joint member rotatably and axiallydisplaceably mounted on each of said arbors, said joint members beingreceived respectively in said cylindrical spaces, said hub having a freeend formed with a spherically convex axial bearing surface having acenter of curvature located at the point of intersection of thelongitudinal axis of said hub and the axes of said joint members, andsaid one joint half being formed with a support bearing surfacecooperatively engaging said axial bearing surface.

2. Coupling according to claim 1 wherein said support hearing' surfaceis planar.

3. Coupling according to claim 1 wherein said support hearing surface isformed on an inner end face of a central cover sealingly secured to aside of the one joint half at which a shaft associated with said jointhalf is attachable.

d. Coupling according to claim l, including an annular sphericallyconcave axial bearing surface formed at the free end of said hub facingsaid center of curvature and having a radius of curvature equal to thedistance from said concave axial bearing surface to said center ofcurvature, and further including a spherically convex support bearingsurface, having substantially'the same radius of curvature of saidconcave axial bearing surface, formed on said one joint half andcooperatively engaging said concave axial bearing surface.

5. Coupling according to claim t, including a shaft stub memberextending from said hub, said convex and concave axial bearing surfacesbeing formed on a bearing head secured to said shaft stub member, saidbearing head being fittingly received with clearance between saidsupport bearing surfaces formed on said one joint half.

6. Coupling according to claim 5 wherein said one joint half is formedwith a cavity having an opening through which said shaft stub memberextends into said cavity, and'including a ring secured to a'transversewall of said one joint half and disposed coaxially to said opening, saidconvex support bearing surface being formed on said ring.

7. Coupling according to claim 5 wherein said bearing head is threadedlysecured to said shaft stub member.

1. Constant velocity joint coupling comprising a pair of joint halves,one of said joint halves being formed with a plurality of axiallyparallel concave race surfaces defining a number of cylindrical spacestherebetween; and the other of said joint halves including a hub havingat least three arbors extending radially in stellate form therefrom, anda spherically convex roller-shaped joint member rotatably and axiallydisplaceably mounted on each of said arbors, said joint members beingreceived respectively in said cylindrical spaces, said hub having a freeend formed with a spherically convex axial bearing surface having acenter of curvature located at the point of intersection of thelongitudinal axis of said hub and the axes of said joint members, andsaid one joint half being formed with a support bearing surfacecoOperatively engaging said axial bearing surface.
 2. Coupling accordingto claim 1 wherein said support bearing surface is planar.
 3. Couplingaccording to claim 1 wherein said support bearing surface is formed onan inner end face of a central cover sealingly secured to a side of theone joint half at which a shaft associated with said joint half isattachable.
 4. Coupling according to claim 1, including an annularspherically concave axial bearing surface formed at the free end of saidhub facing said center of curvature and having a radius of curvatureequal to the distance from said concave axial bearing surface to saidcenter of curvature, and further including a spherically convex supportbearing surface, having substantially the same radius of curvature ofsaid concave axial bearing surface, formed on said one joint half andcooperatively engaging said concave axial bearing surface.
 5. Couplingaccording to claim 4, including a shaft stub member extending from saidhub, said convex and concave axial bearing surfaces being formed on abearing head secured to said shaft stub member, said bearing head beingfittingly received with clearance between said support bearing surfacesformed on said one joint half.
 6. Coupling according to claim 5 whereinsaid one joint half is formed with a cavity having an opening throughwhich said shaft stub member extends into said cavity, and including aring secured to a transverse wall of said one joint half and disposedcoaxially to said opening, said convex support bearing surface beingformed on said ring.
 7. Coupling according to claim 5 wherein saidbearing head is threadedly secured to said shaft stub member.